My Yuasa seems to be getting a bit tired. I was going to replace it with a Odyssey PC310, but the retailer was out of them and the specs on that battery aren't so great (lower CCA than the Yuasa). What I'm really looking for is some increased capacity. I really can't find a Deka retailer.

The retailer (Batteries Plus) stocks a direct AGM replacement (Xtreme Permaseal, Taiwan). I like that it is AGM, but am hesitant to get an off-brand.

I'm considering a LiFEPO4 (Shorai, Antigravity, etc), but researching that is giving me a headache. The plus side is that I can put a more potent battery in the same space.

My Yuasa seems to be getting a bit tired. I was going to replace it with a Odyssey PC310, but the retailer was out of them and the specs on that battery aren't so great (lower CCA than the Yuasa). What I'm really looking for is some increased capacity. I really can't find a Deka retailer.

The retailer (Batteries Plus) stocks a direct AGM replacement (Xtreme Permaseal, Taiwan). I like that it is AGM, but am hesitant to get an off-brand.

I'm considering a LiFEPO4 (Shorai, Antigravity, etc), but researching that is giving me a headache. The plus side is that I can put a more potent battery in the same space.

I researched this ad naseum a year ago, and took a LOT of notes on my learnings... see my linky HERE and search for Battery:

And here is the shorter version of my LiFePO4 mod I ended up with including pictures.

Keep in mind that this was a year ago and much has changed with the LiFePO4 vendors, quality, etc.

Hands down I would get a LiFePO4 (let's just call it Lithium) if I was to do it again. Simply because of the high cranking capacity and the fact that lithiums are SO small you can get a lot more capacity that you really need. They are only good for cranking amps (as opposed to a deep cycle), meaning don't run them down by using accessories without the motor running, then recharge them, or you will have problems, this chemistry is only for cranking amps. I know this has let people down and some don't like them because of that. They are not the same as lead acid.
Also, if I rode in a really cold climate (well below freezing) I might also think twice. Those are the only drawbacks IMHO (besides $$$).

As to brands, it changes a lot. A relative new brand (from a Colorado company) is EarthX which I see inmate herrhelmet is selling is now selling instead of the brand I bought from him a year ago. It has some cool balancing circuitry built into it and I think that is the one I would buy, but I have done NO research on it's reliability which is key.

Matter of fact it's 10 degrees F outside (30 F in my garage) and my bike hasn't been started for a month, and I just went out and started it up, fired up on the 2nd crank.

I'm leaning toward a lithium, but reliability is my #1 priority. (which is why I was headed toward the Odyssey in the first place). Other than perhaps being the best known and having what sounds like good customer service, Shorai seems to have some quality issues and exaggerated specs. I like your point about the A123s having a good track record. But they also are geared more toward cranking amps than capacity. I'm hoping it is moot, since I would fit the largest Li battery that would fit. This would hopefully give me extra reserve and extra CCA to minimize cold start issues with the Li battery. I'm leaning toward 12/18 cell replacements, some of which have 300+ CCA.

I like that the EarthX batteries have the the balancing circuit. But even there, it is a recent add-on and I wonder if the benefits of it are outweighed by an additional, relatively untested, potential failure point. EarthX and Antigravity are currently my frontrunners.

Much of my miles are commute miles with the bike idling. With my heated grips and lights, the voltage will drop down to about 12V at stoplights. The bike has no problem at speed, but some added reserve capacity would bring some peace of mind. The Li batteries can give me that reserve capacity, but I might be losing some peace of mind based on the numerous failures I've read about.

Add the mud and IMO, if you aren't scared, you aren't paying attention.

We had to practically crawl through the icy and deep mud spots. The mud was worse than the ice, because it was still frozen about 3 or 4 inches down.
Picked it up on the open gravel stretches, but I got pretty nervous whenever we got into a shaded section.
It was great to get out though..

__________________
IBA#32778 2008 R1200GSA 2007 G650XChallenge
No man is as good as he ought to be, and few men are as bad as they seem.. (from a early 1900s post card found in Perry, Missouri..)

Your idea of a great ride is a bit more hairy chested than mine. Yeah, I'll bet you were nervous at the shaded areas.

Part of it is mud consistency. Our mud here is often something which, even in fairly shallow doses, fouls to the point of immobility, even serious 4 x 4 trucks. And yeah, I've fallen into those traps. Only way out is to DRAG the bike on its side out of the area.

I'm leaning toward a lithium, but reliability is my #1 priority. (which is why I was headed toward the Odyssey in the first place). Other than perhaps being the best known and having what sounds like good customer service, Shorai seems to have some quality issues and exaggerated specs. I like your point about the A123s having a good track record. But they also are geared more toward cranking amps than capacity. I'm hoping it is moot, since I would fit the largest Li battery that would fit. This would hopefully give me extra reserve and extra CCA to minimize cold start issues with the Li battery. I'm leaning toward 12/18 cell replacements, some of which have 300+ CCA.

I like that the EarthX batteries have the the balancing circuit. But even there, it is a recent add-on and I wonder if the benefits of it are outweighed by an additional, relatively untested, potential failure point. EarthX and Antigravity are currently my frontrunners.

Much of my miles are commute miles with the bike idling. With my heated grips and lights, the voltage will drop down to about 12V at stoplights. The bike has no problem at speed, but some added reserve capacity would bring some peace of mind. The Li batteries can give me that reserve capacity, but I might be losing some peace of mind based on the numerous failures I've read about.

I'm following your quest with interest Marc. I stopped at Cycle Gear to ask about the Yuasa that's listed in this thread on page 1. The manager showed me a Megaboost with the same number. He says it has a life time warranty and even if I sat it in the lot with all the lights and accessories on with the bike off and it wouldn't start I'd get a new one for free. I obviously wouldn't do that of course. I'm a fan of AGM myself. This I believe is a sealed gel type. I keep both bikes on a tender whenever they are in the garage.

At this point I'm debating between the EarthX ETX18B and the Antigravity YTZ10S-12. I really would have liked to just get the Odyssey and be done with it, but I'm not sure the PC310 is the best option. But I still may go that route as it is a known quantity.

I like the benefits of LiFEPO4 batteries and the ability to get more storage/reserve in the same amount of space (or if you would rather save weight and space). Not really new technology, but relatively new to motorcycles with some growing pains. That's my only hesitancy. Of course the original Exide with time tested lead-acid technology didn't exactly distinguish itself in X-Challenges.

Hmmmm, I may have just talked myself into the EarthX . . .

Edit: Just placed the order for the ETX18B because, because, ah heck I dunno why. I guess I'll see how it works out.

I got the EarthX battery (ETX18B) today and installed it. I got it from motolithium.com (herrhelmet in Vendors) for about $200 shipped. It is a snug fit, but works fine. I snapped some photos if anybody is interested.

The first several pics show the size difference. The new battery only weighs about 2 pounds.
It's smaller in dimensions, other than height (see below). This makes for a snug fit in the battery box, but you don't really have to force it. I still used the rubber battery tie down, but it really isn't necessary. You need to route it over the terminal rather than over the top due to the snug fit. You can also see the foam supplied with the battery should you need to secure it further. I only used a couple.

Here's a pic of the current Yuasa in the battery box (excuse the rat's nest of extraneous wires):

Here's how the EarthX battery fit:
And the final fit, with some of my rat's nest tucked into the new found space:

At this point, I can only say it fits and starts the engine. I can't really endorse it until it lasts several years. But if it truly is similar to an 18Ah battery, I'll feel a little better using my heated gear and lights during my cold commutes. This type of battery should tolerate a partial draining better. I'm thinking I can feel a bit more comfortable if I see the battery going down to 12.0 volts, knowing I'm probably not hurting the battery. I'll still be watching that voltmeter. Time will tell.